Some results on the deductive structure of join dependencies

Artikel i vetenskaplig tidskrift, 1984

Among the many different data dependencies defined, the so-called join dependencies play a central role, since they explicitly capture lossless join properties for relation schemes. In this paper we state some inference rules for join dependencies and embedded join dependencies. A set of two rules is shown to be complete for monadic join dependency inferences (inferences from a single dependency). Furthermore, it is shown that there is no finite set of inference rules that is complete for embedded join dependencies.